Today, I continue the front yard design for a yard with black walnuts from the last post.
The Tough choice
This design desperately needs some evergreen shrubs. Finding an evergreen shrub that tolerates Juglone and shade is the tricky part. Besides hemlock, there really are not any other ones listed in the Juglone tolerant lists.
However, that does not mean there are not ones that will work. For instance, yews are not supposed to work under black walnut, but I know of several that have for the last decade.
But to be a bit safer, I will pick a plant that is not on most sensitive lists, Green Velvet boxwood (Buxus ‘Green Velvet’ ). In fact I have found a few sources that say it is fine under Black Walnuts.
As boxwood have a very dense matt of roots, if their planting holes are dug extra deep and wide and all tree roots are cut out and then they are filled with some good old store bought garden soil, there is a good chance the boxwood will be fine for a long time even if they are indeed bothered by juglone.
If you are a SCARE-DEE CAT and don’t want to use a plant not on a safe for Walnut list, Gro-Low Sumac (Rhus aromatica ‘Gro-Low’) could be substituted. They are not evergreens, so there will be less color in the winter. They do spread a bit further, so if you want to save a few bucks you could plant fewer of these spaced further apart.
Now we can add the last plant, some flowing beds of Japanese pachysandra (Pachysandra terminalis) ground cover. This does great in shade and is not bothered by black walnuts. We could just fill all the beds with this ground cover to be simple. However, I like adding it in flowing shapes especially to complement the dry creek bed.
So that’s the design. Here is a perspective to help you visualize what it would look like a few years after planting. Just like those above, you can click on it to enlarge it.
After having all my rhododendrons, kalmias and pieris die due to my own ignorance of the effects of our BW tree, I have spent literally thousands of hours researching evergreen shrubs that are appropriately sized for foundation plantings, somewhat shade tolerant, hardy in zone 5b AND juglone tolerant. I was so happy to find this page! Please, can you update on how the box woods are doing?
Jim, where have you been all my life (ok, for the 14 years I’ve been trying to garden under the enormous black walnut in my backyard)? These two posts have been tremendously helpful, particularly with suggestions for evergreens and shrubs that will tolerate shade and the BW. I’ve had consultations with my local nursery and nobody has yet given me the info you’ve laid out here. Thanks.
You are very welcome.
Jim, this is a beautiful design! Very well done.
Thanks Jean.